1. Université Sorbonne Paris Nord, LIPN, CNRS UMR 7030, F-93430 Villetaneuse, France
2. Université de Lorraine, CNRS, Inria, LORIA, F-54000 Nancy, France
3. Nantes Université, École Centrale Nantes, CNRS, LS2N, UMR 6004, F-44000 Nantes, France
4. School of Computing and Information Systems, Singapore Management University, Singapore